加藤 由花

We, RSi (Robot Service Initiative) organization, have been developing a common network based robot service platform, named RSNP (Robot Service Network Protocol) since 2004. As spreading actual use of RSNP, strong requirements are raised on the push communication in limited conditions such as fewer operators and/or limited resources, and on the robot service integration with various devices supported by the other robot platform, such as RTM (Robot Technology Middleware), particularly. In this paper, we clarified these requirements and solved them by pseudo PUSH communication method, by introducing multimedia/sensor profile and by building RSi/RTM gateway. Moreover, we evaluate the effectiveness of the proposed scheme through the performance experiments. And also these results have been also reflected in RSNP 2.0, the latest specification.

This paper proposes a network service platform for developing network services using real-world and virtual-world data efficiently. The proposed platform. collects the data front various kinds of devices, including cell phones, sensors and robots, and provides general APIs to implement network applications and services using the data. This paper also shows an application example of the proposed platform.

In order to facilitate the education by Project Based Learning (PBL) method, it is very important for the instructors to share the information about the activities of all the students. It is, however, difficult for the instructor to attend every team meeting and take care of all the students individually, and it is much more important to keep track of the activities of the students in teams. Hence, we have developed a PBL facilitation system which visualizes the projects and provides web based tools to help students work collaboratively. In this paper, we report on a PBL course that uses the above system, and investigate its usefulness.

This paper proposes a rate control method providing the maximum subjective video quality using the minimum transmission rate for streaming video services on mobile data terminals. At that time, because user perceptive video quality differs greatly with video contents, we need to consider the control method with reference to them. In this paper, we conduct subjective assessment and analyze the relationship between video content and subjective video quality The proposed scheme makes it possible to provide high-quality streaming services under the condition of using limited fixed-size monitors.

This paper proposes an efficient construction process for small-scale network systems, including name services, mail services and so on. In the research field of software engineering, many studies have been made of software development processes, and high quality software systems have been efficiently developed by using them. The proposed scheme applies software development processes to network system construction, and defines the process which consists of "requirements", "design", "implement", "testing" and "deployment" processes. This paper also shows an application result of the proposed scheme to a network course at a graduate school.

The authors have proposed a music delivery system JAMS (JAMais vu System), which uses ad-hoc networks with mobile devices for the localization services. In this paper, they focus on a cache management scheme for JAMS to deliver music files efficiently. The proposed scheme makes it possible to manage cache files, robustly by using adaptive cache delivery according to each node request. In addition, the authors conduct a simulation experiment and obtain access failure ratio of music files under various system conditions. The simulation results indicate that the proposed scheme is suitable for the system using localization services.

This paper analyzes the relationship between video content and subjective video quality, and applies the results to rate control methods for streaming video services. In this analysis, we classify video programs into some groups in which large majority of users feel the same video quality. We determine the relationship by conducting an experiment with method of paired comparisons, and express that as equations by multiple linear regression analysis. Moreover, we apply the results to an actual encoding system, and we found out that the proposed schemes makes it possible to provide high-quality streaming services under various system environments.

The present paper analyzes the relationship between video content and subjective video quality for user-centered streaming services. In this analysis, we conduct subjective assessments using various types of video programs, and propose a method of classifying video programs into a number of groups that are thought by a large majority of users to have the same video quality. Control to a high level of user satisfaction can be performed by applying a different control method to each group obtained using the proposed method. In addition, we demonstrate the necessity of rate control according to video content by comparing a classification result based on vision parameters with the classification result based on the assessment result.

This paper analyzes relationship between video contents and subjective video quality for user-oriented streaming services. In this analysis, we conduct subjective assessments by using various kinds of video programs, and propose a method classifying video programs into some large majority of users feel the same groups in which a large video quality. The control with a high level of user satisfaction can be done by applying different control method to each group obtained from the proposed method. We also show the necessity of rate control according to video contents by comparing a classification result based on vision parameters with that based on the assessment result.

This paper analyzes relationship between video contents and subjective video quality for Internet broadcasting, and applies the results to the rate control methods. In this analysis, we classify video programs into some groups in which a large majority of users feel the same subjective video quality. We investigate the relationship by conducting an experiment with method of paired comparisons, and express that as equations by multiple linear regression analysis.

This paper proposes an advanced movie recommender system. The system is primarily based on the content-based collaborative filtering or hybrid filtering technique. The distinctive point of this system lies in an improved neighborhood formation method in order to get high-quality neighbors. Current hybrid systems only use user's opinions as user's rating values in selecting neighbors. That causes loss of user preference features, and tends to provide poor quality neighbors. The proposed system uses the user's opinions on various features of user preferences in selecting neighbors. That results in high-quality neighbors and high-quality recommendations will be obtained accordingly. An experimental movie recommender system, called Advanced Yawara system has been developed to prove the effectiveness of the method. The evaluation results show that the Advanced Yawara system provides higher quality of recommendations than current hybrid systems.

This paper proposes a streaming video system adapting to various system environments. Until now, many studies of adapting QoS (Quality of Service) control methods have been made in the area of streaming video technologies in the Internet. However these methods have not been able to provide sufficient service quality to system users under recent diversification of system environments. We therefore design the system based on three ideas. First, the system conducts switching of streaming servers. This switching makes it possible to combine multiple control mechanisms and to use the combination for QoS control. Second, the system adopts simple estimation methods of network conditions. Estimation accuracy is gradually modified while users are watching streams. Third, the system notifies information of network conditions to system users. This makes it possible to provide streaming services with high level of user satisfaction. We conducted implementation experiments using the proto-type system. From these experimental results, we found out that the proposed system was adaptable to various system environments and that the QoS notification decreased the level of user dissatisfaction of service quality.

This paper proposes a streaming video system which can be used in various system environments. This system has three features for providing real-time video delivery services in the Internet. The first is to use QoS (Quality of Service) control rules adapting to the system environments. The second is to improve estimation accuracy of the network conditions while a user is watching a stream. The third is to notify QoS degradation factors to the user actively. These features make it possible to provide streaming services with a high level of user satisfaction. This paper also shows an experimental system in our laboratory as an implementation example.

This paper proposes a video delivery method, which makes it possible to glance at high quality videos while working or studying in a PC monitor The target is a small-scale best-effort network, such as networks in SOHOs and laboratory rooms in universities. This method reduces video frame rate when users do not fix their eyes on the video, and delivers high quality, video when they fix their eyes on it. This is based on the idea that high quality videos are not necessary while they do something except watching a video. For detecting the watching, we use mouse clicks. As a result, we can reduce useless video delivery traffic when concentrating on other works and use bandwidth resources effectively.

コンピュータネットワーク上に多くの分散マルチメディアシステムが導入されるにつれ，利用者に対して提供されるサービスの品質（Quality of Service: QoS）に対する注目が高まってきている．我々はこのサービス品質をアプリケーションQoSと定義し，システム環境に対して適応的なアプリケーションQoS制御を実現する，アプリケーションQoS管理システム（application QoS Management System: QMS）の研究を進めている．QMSはアプリケーションQoSを制御対象とするが，計算機やネットワーク資源が動的，静的に変化する実システム環境に適応するため，複雑なモデル化をともなわないフィードバック型の簡易な制御方法を採用する．そのため，ネットワークレベルの制御とアプリケーションレベルの制御を組み合わせることによって，システム全体としてのアプリケーションQoSの向上を図る．ここでQoSの管理はシステム管理者がQMSに設定するQoS管理ポリシーに基いて行われるが，複数のアプリケーション間でQoS要求に対する整合性を保ちながら制御の優先順位を決定することは困難である．本稿では，この設定作業を支援するQoS管理ポリシー設定手法を提案し，DV転送システムを利用した実験システム上への実装結果を紹介する．さらに，この実験システムを利用してQMSの性能評価実験を行ったので，その結果を報告する．As a large number of distributed multimedia systems are deployed on computer networks,Quality of Service (QoS) for an application becomes more important.This paper defines it as application QoS,and proposes the application QoS Management System (QMS).Its control targets are application QoSes and it controls the QoSes according to the system environment.At that time,the system adopts simple control methods without complicated modeling in order to adapt QMS to practical system environment.This is because system resources always change dynamically and statically on the practical environment.In addition,QMS aims to manage application QoSes in the whole system;therefore, it does the QoS control by combining network level control method with application level control method.This QoS management is done according to QoS management policies which the system administrator sets to QMS.However, it is difficult to decide the control priority while negotiating QoSes among many applications.This paper proposes the method setting the QoS management policy,and describes the implementation results on the prototype system using digital video transport system.Moreover, we show the experimental results of QMS performance evaluation by using this prototype system.

As a large number of distributed multimedia systems are deployed on computer networks, Quality of Service (QoS) for users becomes more important. This paper defines it as application QoS, and proposes the application QoS Management System (QMS). It controls the application QoS according to the system environment by using, simple measurement-based control methods. QMS consists of three types of modules. These are Notificator module detecting QoS deterioration, Manager module deciding the control method according to the application management policies, and Controller module executing the control. QMS manages the application QoS by communicating between these modules distributed on the network. Moreover, this paper especially focuses on the function setting QoS management policies to QMS and proposes the setting method. By simulation experiment, we confirmed that the system made it possible to negotiate the QoS among many applications and it was able to manage the whole applications according to the policies.

一般家庭を対象とした双方向マルチメディアサービスのためのシステム設計法について一提案を行う. インフラとしてATMネットワークを適用し, サービスアプリケーションの通信に関する特徴からデータタイプ別にVC (Virtual Channel) を設定する手法において, ネットワークリソースの効率的な利用を図り, かつユーザにサービスに対する不快感を与えないシステム構成, およびネットワーク, アプリケーションの設計について報告する. また, 実システムによりデータを取得し, 品質評価を行い, 設計モデルの妥当性を検証していく.

This paper proposes self-sizing network operations to innovate circuit/path operations in ATM networks. The self-sizing network is a new concept in traffic operations that uses rapid and flexible resource assignment to meet the traffic demand. These operations support functions such as traffic management, resource design, and administration, failure and congestion operations and service operations by making full use of network flexibility and simplification and recent technologies for enlarging system capacity. They are expected to overcome foreseeable future issues, e.g., the varieties of services and the unpredictability of the demand in the future, as well as the complexity of the traffic, circuit, and path dimensioning, and administration based on these issues. In particular, this paper describes the algorithms that adapt VP capacity to traffic in traffic management operations (Step 1) and their system implementations. The implemented system aims at customizing algorithms and encapsulating the components of algorithms and adopts TMN to follow the OSI standard.

This paper proposes self-sizing network operations to innovate circuit/path operations in ATM networks. The self-sizing network is a new concept in traffic operations that uses rapid and flexible resource assignment to meet the traffic demand. These operations support functions such as traffic management, resource design, and administration, failure and congestion operations and service operations by making full use of network flexibility and simplification and recent technologies for enlarging system capacity. They are expected to overcome foreseeable future issues, e.g., the varieties of services and the unpredictability of the demand in the future, as well as the complexity of the traffic, circuit, and path dimensioning, and administration based on these issues. In particular, this paper describes the algorithms that adapt VP capacity to traffic in traffic management operations (Step 1) and their system implementations. The implemented system aims at customizing algorithms and encapsulating the components of algorithms and adopts TMN to follow the OSI standard.